Quality issues on LED tubes?

LED tubes, are they good or bad? An interesting discussion that I recently read on social media was about this issue. It brought me to this new blog because it is an interesting discussing where things are not always being clearly communicated. In the past the company I work for did a project on this and the conclusions where not that positive. However the development of LED is very fast and with the current technology most of these negatives have been solved. A good look and at LED tubes is necessary.

The first argument that LED tube manufacturers use is do not look at lumen but look at Lux. This is a partly valid argument, as are most arguments. Yes the lux value on the area that you want to light up is important but you also have to consider other factors. If you look at a fluorescent luminaire for offices it is generally designed to light an area but also the surrounding area’s. So not only the desk you are working on, where you need the minimum lux level (by directives) but also the surrounding area and the walls.

If you replace in a good fluorescent luminaire a Fluorescent tube with a LED tube in most cases (depending on the emission area of light) the wall’s are no longer fully lit. So this means that the light level on the work surface can be as required but the total illumination of the room is decreased. Is that important? That depends on the enduser. Please note that they eye (and your mind) is most comfortable in a evenly lit space. If that is not the case you may become tired quicker due to your eyes having to adjust to different light levels constantly.

So it depends a lot on what you are lighting up and what your goals are. In cases the original fluorescent luminaries might not have done a good job in te first place. I have also seen those instances where amount of light was so much less that removing a few fluorescent tubes would have had the same savings. Anyway the issue is to make sure that the light goes there where it is needed.

Second argument is that the life time of the LED tubes is much longer than that from fluorescent tubes. This is a bit more difficult argument since it comes back to the quality of the products used. Agreed, when using the cheapest fluorescent tubes you can expect life times of 10k hours. To be honest we have also seen a lot of LED tubes where claimed 100k hours or even more with actual life’s of less than a few hundred hours. Currently this quality issue has improved.

The main problems are caused due to heat in the tube. Therefore the most effective solutions are those where there is a separate driver. That has some complications as well but these have the best chance of a longer life and the lowest lumen depreciation. The alternative is to use more expensive fluorescent tubes. There are fluorescent tubes on the market that have a life expectancy of over 40k hours. These lamps are still a lot cheaper than the LED tubes. There some points to consider however and that is the number of switchings. This can also be a problem for drivers so this is an issue that is for both products.

In the market we have also seen that the lifetime claims on LED tubes is taken more serious. Manufacturers have improved the products but reduced the life expectancy claims as well. This shows that the LED market is growing up and is starting to professionalize.

The temperature argument. This one is very valid. The colder you keep the LED the beter it performs. In this case the fluorescent tube will loose out quickly. For fluorescent tubes you need to take extra measure to make sure it get nicely warm quickly. LED on the other hand wants to stay cold. In cold storage for example LED will easily outperform fluorescent and replacing these fluorescent tubes by LED tubes is a no-brainer.

The pricing argument. This one is very often used by fluorescent manufacturers I presume. These tubes are very cheap and LED tubes are have a much higher cost. The important thing here as well is to look at the whole picture and in my opinion you should always weigh both alternatives. Simply looking at the current installation and making a calculation on that and comparing with LED is not enough. Also compare with a new efficient T5 installation as well or new LED luminaires. You might be surprised about the difference.

Anyway do look at the whole life expectance of the installation and also take in mind how long the installation is actually going to be used and make a decision. It is not easy to say what is better however the scale is moving quickly to generally LED.

Argument; replacing a fluorescent tube with an LED tube is more environmentally friendly than replacing the whole luminaire. In first instance this sounds very liable but is it? If you make a good light plan based on LED luminaires you might find that you need less luminaires to get the same effect. That could very well also reduce energy consumption even further. So also on this issue a clear evaluation will give the right answer.

The arguments that I always miss in the discussion is who is taking responsibility? In many cases the LED tube is supplied and an electrician modifies (removes or bridges the control gear) the luminaire. He might not be aware that he is now responsible for full compliance of this new product with legislation. LED Tube manufacturers do not touch this issue when they sell the product.

Another issue is the weight of the tubes. If the product does comply with the LVD it is not overweight for the lamp holders. What happens in old luminaries, especially those that have been used with fluorescent tubes, the lamp holders become brittle. This can very well result in tubes faling out of the luminaire because the lamp holders cannot support the weight anymore. A serious issue when these tubes are falling in a warehouse from 12 meters height. So replacing the lamps does have more complications.

Conclusion; as in many cases there is no clear conclusion in my opinion. The decision must be taken by the user. Important is that the user is aware of all issues involved and can make a decision based on all issues concerned.